CAJ | 학술논문

采用水热法合成纳米LiFePO4材料并研究了反应溶液pH值和温度对LiFePO4材料颗粒形貌、微观结构和电化学性能的影响。控制Li∶Fe∶P摩尔比为3∶1∶1，按照先混合LiOH与H3PO4溶液后加入FeSO4溶液的投料顺序，在溶液pH值为6.0以上可以得到结晶度好且比容量较高的纳米级LiFePO4材料。pH为6.0和180℃条件下得到的是LiFePO4纳米薄片，调整反应溶液pH值为中性和弱碱性，或控制反应温度在140℃以下或者200℃以上，LiFePO4材料可能是方形或者形貌不规则的纳米颗粒。电化学测试结果表明，颗粒形貌方形或者不规则的LiFePO4材料大电流放电性能优于薄片状纳米材料。
채용수열법합성납미LiFePO4재료병연구료반응용액pH치화온도대LiFePO4재료과립형모、미관결구화전화학성능적영향。공제Li∶Fe∶P마이비위3∶1∶1，안조선혼합LiOH여H3PO4용액후가입FeSO4용액적투료순서，재용액pH치위6.0이상가이득도결정도호차비용량교고적납미급LiFePO4재료。pH위6.0화180℃조건하득도적시LiFePO4납미박편，조정반응용액pH치위중성화약감성，혹공제반응온도재140℃이하혹자200℃이상，LiFePO4재료가능시방형혹자형모불규칙적납미과립。전화학측시결과표명，과립형모방형혹자불규칙적LiFePO4재료대전류방전성능우우박편상납미재료。
LiFePO4 nano-materials for Li-ion battery were prepared by hydrothermal method, and the effects of pH value and reaction temperature on the particle morphology, structural composition and electrochemical properties of the LiFePO4 material were investigated. With the final molar ratio of 3∶1∶1 for Li∶Fe∶P by adding FeSO4 solution into the mixture of LiOH and H3PO4 solutions, nanoparticles of LiFePO4 with wel crystal inity and high special capacity were obtained by regulating pH values to above 6.0. The flake-like LiFePO4 nano-materials were prepared at pH 6.0 and 180 ℃. The particle morphology was rectangular-like or irregular if regulating pH values to above 7.0 or control ing hydrothermal reaction temperatures to higher than 200℃ or below 140 ℃. The electrochemical results show that the high rate capability of LiFePO4 nano-materials with rectangular-like or irregular shape is better than that of flake-like nano-materials.